"Not Simple" is a manga written and illustrated by Natsume Ono, known for its intricate narrative structure and emotional depth. The story revolves around Ian, a young man with a troubled past, and his journey to reconnect with his estranged sister, Kylie. The narrative unfolds non-linearly, weaving between past and present to reveal the complexities of Ian's life and the events that shaped him.

Ian's childhood is marked by abandonment and hardship. His mother, Claire, leaves him and his sister in the care of their abusive father, who eventually abandons them as well. The siblings are separated, with Kylie sent to live with relatives while Ian is left to fend for himself. Despite the separation, Ian remains determined to find Kylie, driven by a deep sense of responsibility and love for his sister.

As Ian grows older, his quest to reunite with Kylie takes him across continents, from Australia to the United States. Along the way, he encounters various individuals who influence his journey, including a journalist named Jim, who becomes a key figure in documenting Ian's story. Jim's perspective provides an outsider's view of Ian's struggles, adding layers to the narrative as it shifts between Ian's personal experiences and Jim's observations.

The story delves into themes of family, loss, and resilience, exploring how Ian's past continues to shape his present. Flashbacks reveal the emotional and physical abuse Ian endured, as well as the fleeting moments of kindness that offered him hope. These memories are juxtaposed with his present-day challenges, highlighting the enduring impact of his early trauma.

Kylie's perspective is also explored, though more sparingly, offering glimpses into her life after being separated from Ian. Her experiences are marked by a sense of guilt and longing, as she too grapples with the consequences of their fractured family. The siblings' parallel journeys underscore the shared pain and unbreakable bond between them.

The narrative's non-linear structure serves to emphasize the fragmented nature of Ian's memories and the complexity of his emotional landscape. Each revelation adds depth to the characters and their relationships, painting a poignant picture of a man striving to overcome his past and find closure.

"Not Simple" is a deeply moving exploration of human resilience and the enduring power of familial bonds, told through a narrative that is as intricate as it is heartfelt. The characters' struggles and triumphs are rendered with a quiet intensity, making the story a compelling and emotionally resonant read.